● Features and scope of application:

Higher hardenability, machinability and weldability is good, but sensitive to notch and hydrogen embrittlement (including environmental hydrogen embrittlement). 30CrMnSiNi2MoA is suitable for high strength connectors and shaft parts and other important structural components.

● Chemical composition:

Carbon C: 0.27 ~ 0.34

Si: 0.90 ~ 1.20

Mn: 1.00 ~ 1.30

S: sulfur 0.020 or less

P P: 0.020 or less

Chromium Cr: 0.90 ~ 1.20

Ni: 1.40 ~ 1.80

● Mechanical properties:

Tensile strength σB (MPa) : 1)1767; 2) 1627

Elongation δ5 (%) : 1)12; 2) 13

Section shrinkage ψ (%) : 50

Impact toughness αku (J/cm2) : 1)79; 2) 90

Sample size: bar

● Heat treatment specification and metallographic structure:

Heat treatment specifications: 1)890 ~ 900℃ oil quenching,200 ~ 300℃ tempering, air cooling; 2) Heated at 890 ~ 900℃, quenched into 210 ~ 280℃ salt tank isothermal for 1H, air cooled, and then tempered at 200 ~ 300℃, air cooled.

Metallography: 1) hot rolling or cold rolling after high temperature tempering to pearlite; 2) Normalizing and high temperature tempering is tempered soxhlet; 3) Flake pearlite and ferrite after isothermal annealing; 4) The normal state is martensite and bainite; 5) The service state is tempered martensite.

30CrMnSiNi2MoA High Strength Steel